Method and apparatus to obtain the agitation of electrolyte inside a lead-acid storage battery

ABSTRACT

The invention concerns a method to obtain the agitation of the electrolyte inside a lead-acid storage battery comprising at least one canalization duct ( 4 ) of electrolyte which is immersed inside the storage battery. Said method consists in: connecting said canalization duct ( 4 ) of electrolyte with a device ( 50 ) realizing repetitive and alternative cycles of pressure decrease and of return to the initial pressure in the section of tube ( 40, 41 ) which connects said device to said canalization duct, said cycles causing the movement of the electrolyte being sucked and dropped respectively in said canalization duct.

The invention concerns a method to realize the agitation of electrolyteinside a lead-acid storage battery.

It is a known fact that during the recharging process of the lead-acidstorage battery fumes develop, especially hydrogen, which sometimesremain adherent to the plates, thus preventing the dissolution of thelead sulfate and the restoration of the balance in the battery. It isimportant then to activate a circulation or an agitation of electrolytewhich can prevent fume bubbles from forming and accumulating during thecharging process.

According to a known technique, in order to overcome such incoveniences,and also to accelerate the charging times, the agitation of electrolyteis achieved by blowing air inside the box containing the electrolyteduring the charging process. In such a way, a mixing of electrolyte,with a consequent uniformity of its density at the various levels of thestorage-battery is obtained. The purpose which the invention proposes isto obtain an agitation of electrolyte inside a lead-acid storage batteryduring the charging process wherein such an agitation occurs withoutblowing air or other gasses from the exterior inside the electrolyte.

The main purpose of the invention and others which will be betterpointed out hereinafter, are achieved by the proposed method to obtainthe agitation of electrolyte inside a lead-acid storage batterycomprising at least one canalization duct of electrolyte which isimmersed inside the storage battery wherein said method is characterizedin that it consists in:

connecting said canalization duct of electrolyte with a device realizingrepetitive and alternative cycles of pressure decrease and of return tothe initial pressure in the section of tube which connects said deviceto said canalization duct, said cycles causing the movement ofelectrolyte by sucking and dropping it respectively, in saidcanalization duct.

Advantageously, during a recharging process one or more storagebatteries are connected to the device of the pressure variation, thesebeing equipped each with one canalization duct, for instance a verticalpipe which sticks out of the lid of the storage battery. With a devicefor the pressure variation during the suction phase of said device, theelectrolyte is made to go up along the canalization duct while, when thepressure returns to its normal values, the electrolyte comes down backto its original level. In realizing this variation of pressure withrepetitive cycles and with a certain frequency, the electrolytecontained inside the storage battery is constantly pushed upwards anddropping down.

The consequent agitation of electrolyte causes a uniformity of densityof electrolyte at the various levels of the box of the storage batteryand also a stripping action on the electrolyte plates with a consequentremoval of possible hydrogen fume bubbles which form during therecharge. This action of movement of electrolyte causes a decrease ofthe charging time and also a better uniformity of the charge of theplates with a consequent extension of the life span of the storagebattery.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specific example,while indicating a preferred embodiment of the invention, are given byway of illustration only, since various changes and modifications withinthe spirit and scope of the invention will become apparent to thoseskilled in the art from this detailed description and from the drawings.

BRIEF DESCRIPTION OF THE INVENTION

FIG. 1 shows in a prospective view three storage batteries connectedwith a device suited to realize the method of agitation of electrolyteaccording to the invention;

FIG. 2 shows in a cross-section an application sketch of the methodaccording to the invention before the decreasing phase of the pressureinside the storage batteries;

FIG. 3 shows the drawing of FIG. 2 during the phase of maximum decreaseof the pressure inside the storage battery.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the mentioned Figures, it can be observed that eachcontainer, indicated as a whole with 1, presents a box 2 and a lid 3sealed on box 2. Each storage battery 1 is also equipped with acanalization duct of electrolyte, indicated with 4. Each duct 4 has aninlet end 8 formed in an opening in the lid 3 and extending into thevessel 2 for receiving liquid therein. Each duct 4 also has a suctionend 9 extending through the opening in the lid 3 to the outside of thevessel 2. Each storage battery also presents a topping up hole for theelectrolyte provided with a seal-tight cap 5 besides the two poles 6 and7. During the recharging phase of the storage batteries, several storagebatteries are connected with one another, each in correspondence withthe canalization ducts 4 by means of tubes 40 and 41 which are connectedto the device 50 which realizes the alterative cycles of the pressurevariation inside each container 1. Tubes 40 and 41 are connected by witha plurality of intermediate tubes 10. Each intermediate tube 10 has afirst end 11 connected to the first tube 40 and a second end 12connected to the second tube 41.

As can be observed in the Figs. from 2 to 3, the device 50 consists of acylinder 51 inside which a piston 52 slides alternatively, driven byknown means not represented in the drawing. In correspondence with thehead of the cylinder there is an opening connected to duct 41 and,therefore, to each canalization duct 4 of electrolyte. As can beobserved in FIG. 3, once piston 52 has moved in the direction oppositeto the entrance duct 41, the electrolyte will raise in the canalizationducts 4 in order to realize a variation in volume whose total value isequal to the variation in volume of the space 53 created by the strokeof piston 52. In the meantime, the air contained in the inner space 54comes out of valve 55. Piston 52 then reverts its stroke, withoutuncovering the port of valve 55 in space 53, so that the intial pressureinside the containers 1 is restored and, therefore, the electrolytedrops down to its inital level, as can be observed in FIG. 2.

It is clear that by varying the frequency of the strokes of piston 52 itis possible to obtain a variation in the frequency of the ascent anddescent of electrolyte and, therefore, of the degree of agitation of theelectrolyte itself. Of course, the devices which realize repetitive andalternative cycles of the pressure decrease and the return to theinitial pressure can differ from the one now described. However, animportant fact is still present, that is in this way the electrolyte isagitated and, therefore, there is a mixing of the electrolyte itself,with a levelling in the electrolyte density and moreover, there will bea removal of possible fume bubbles which had remained adherent to theplates.

What is claimed is:
 1. A method for agitating electrolyte inside a groupof lead-acid storage batteries, comprising the steps of: providing eachof said batteries with a vessel for containing a selected liquid level,a lid with an opening for closing said vessel and having at least onecanalisation duct for carrying electrolyte immersed inside the storagebattery and emerging from the lid, each canalisation duct having aninlet end formed in the opening in the lid and extending below theliquid level for receiving liquid therein and each canalisation ducthaving a suction end extending through the opening outside the vessel,reciprocal means commonly coupled to the suction ends of thecanalisation ducts for cyclically pressurizing and depressurizing theliquid in the canalisation ducts, a portion of each canalisation ductoutside the lid of said storage battery is sized to receive an increasedvolume of the electrolyte during suction performed by said reciprocalmeans, a plurality of tubes having a first tube commonly connecting thesuction ends of the canalisation ducts and a second tube connected tothe reciprocal means, and a plurality of intermediate tubesinterconnecting the first tube with the second tube; connecting each ofsaid canalisation ducts with the reciprocal means through the pluralityof tubes and intermediate tubes for carrying out repetitive andalternating cycles of pressure decrease from an initial pressure andreturning to the initial pressure in a portion of the tubes whichconnects said reciprocal means to said canalisation ducts, said cyclescausing the movement of the electrolyte which is sucked and droppedrespectively in said canalisation ducts.
 2. A method for agitatingelectrolyte within a group of lead-acid storage batteries according toclaim 1, further comprising the step of: cyclically operating thereciprocating means in alternating suction and pressure cycles; saidcycles, causing the movement of the electrolyte in the battery into andout of said canalisation ducts thereby agitating the electrolyte.
 3. Anapparatus for agitating electrolyte in a group of storage batteries,each battery in the form of a vessel for containing a selected liquidlevel and a lid having an opening for closing said vessel comprising: aduct having an inlet end formed in the opening in the lid and extendingbelow the liquid level for receiving liquid therein and said duct havinga suction end extending through the opening outside the vessel;reciprocal means commonly coupled to the suction ends of the ducts forcyclically pressurizing and depressurizing the liquid in the ducts; aportion of each duct outside the lid of said storage battery is sized toreceive an increased volume of the electrolyte during suction performedby said reciprocal means; a plurality of tubes has a first tube commonlyconnecting the suction ends of the ducts; the plurality of tubes has asecond tube connected to the reciprocal means; and a plurality ofintermediate tubes are connected to said first tube and said secondtube.
 4. The apparatus of claim 3 wherein each intermediate tube of saidplurality of intermediate tubes, has a first end connected to the firsttube and a second end connected to the second tube.